將圖像控件綁定到可觀察的集合

Question

我正在嘗試獲取BitmapSource對象的ObservableCollection綁定到WPF表單上的一堆圖像，並且該圖像從不顯示...我驗證了該圖像已加載到屬性中，但是我的綁定必須不正確.... 。應如何編碼綁定路徑？ 我曾經將每個圖像綁定到一堆不同的對象上，但是使用列表要好得多，所以我想用這種方式來綁定它們……

文本框正確顯示了ProgramPath屬性，但我無法綁定圖像源

XAML-在網格內，我有許多彼此相鄰的文本框和圖像

<TextBox HorizontalAlignment="Stretch" Margin="24,2,2,2" Name="TextBoxA" VerticalAlignment="Stretch" 
                          Width="664" >
                    <Binding Path=".[0].ProgramPath" UpdateSourceTrigger="PropertyChanged">
                        <Binding.ValidationRules>
                            <local:ExternalProgramValidator/>
                        </Binding.ValidationRules>
                    </Binding>
                </TextBox>
                <TextBox Grid.Row="1" HorizontalAlignment="Stretch" Margin="24,2,2,2" Name="TextBoxB" VerticalAlignment="Stretch" Width="664" >
                    <Binding Path=".[1].ProgramPath" UpdateSourceTrigger="PropertyChanged">
                        <Binding.ValidationRules>
                            <local:ExternalProgramValidator/>
                        </Binding.ValidationRules>
                    </Binding>
                </TextBox>

<Image Height="16   " HorizontalAlignment="Left" 
                       Margin="4" Name="ImageA" Stretch="Fill" VerticalAlignment="Center" Width="16"                           
                       Source="{Binding Path=.[0].ProgramImage, UpdateSourceTrigger=PropertyChanged}">
                </Image>
                <Image Grid.Row="1" Height="16   " HorizontalAlignment="Left" 
                       Margin="4" Name="ImageB" Stretch="Fill" VerticalAlignment="Center" Width="16"
                       Source="{Binding Path=.[0].ProgramImage, UpdateSourceTrigger=PropertyChanged}"/>

然后我有一個這樣的公開課

public class ExternalProgramsWindowData : INotifyPropertyChanged
{
    private BitmapSource _ExtractPathImage(string fullPath)
    {
        BitmapSource returnedImage = null;

        string pathForImage = string.Empty;
        string[] s = fullPath.Split(new string[] { ".exe" }, StringSplitOptions.None);

        if (s[0] != null)
        {
            pathForImage = s[0] + ".exe";
        }

        if (!string.IsNullOrWhiteSpace(pathForImage))
        {
            System.Drawing.Icon icon = IconExtractor.GetIcon(pathForImage, true);

            returnedImage = System.Windows.Interop.Imaging.CreateBitmapSourceFromHIcon(
                icon.Handle,
               System.Windows.Int32Rect.Empty,
                System.Windows.Media.Imaging.BitmapSizeOptions.FromEmptyOptions());
        }

        return returnedImage;

    }

    /// <summary>
    /// A
    /// </summary>
    private string _programPath;
    public string ProgramPath
    {
        get { return _programPath; }
        set
        {
            _programPath = value;
            Notify("ProgramPath");
            ProgramImage = _ExtractPathImage(_programPath);
        }
    }

    private BitmapSource _programImage;
    public BitmapSource ProgramImage
    {
        get { return _programImage; }
        set
        {
            _programImage = value;
            Notify("ProgramImage");
        }
    }


    #region INotifyPropertyChanged Members

    public event PropertyChangedEventHandler PropertyChanged;

    protected void Notify(string propName)
    {
        if (this.PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propName));
        }
    }

    #endregion
}

在主窗口類中，我將網格綁定到這些類對象的集合

/// <summary>
/// Interaction logic for Window1.xaml
/// </summary>
public partial class ExternalProgramsWindow : Window
{


    public ObservableCollection<ExternalProgramsWindowData> WindowDataList { get; set; }


WindowDataList = new ObservableCollection<ExternalProgramsWindowData>();

        ExternalPrograms_ExternalProgramsGrid.DataContext = WindowDataList;

然后加載集合，並設置ProgramPath屬性，並觸發設置ProgramImage（正確設置為圖像，但窗口不顯示該圖像）

foreach (ExternalProgram program in externalProgramList)
        {
            ExternalProgramsWindowData oExternalProgramsWindowData = new ExternalProgramsWindowData();
            oExternalProgramsWindowData.ProgramPath = program.Path + " " + program.Arguments;


            WindowDataList.Add(oExternalProgramsWindowData);

Answer 1

嘗試通過繼承自定義類將其用作ObservableCollection 。 在上面的代碼中，我看不到可觀察的集合與要綁定的屬性之間的鏈接。

// assuming ExternalProgramsWindowData are your bitmap objects
public class SourceList : ObservableCollection<ExternalProgramsWindowData> {

}

public class ViewModel : INotifyPropertyChanged {

    private SourceList mySourceList;

    public SourceList MySourceList {
         get { return mySourceList; }
         set {
             mySourceList = value;
             FirePropertyChanged("MySourceList");
             }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected void FirePropertyChanged (string propertyName) {

        if (PropertyChanged != null) {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }

}

然后，在實際的綁定中，您將遇到以下情況：

綁定源：對象ViewModel。 綁定的路徑：“ MySourceList”。

我不熟悉ExternalProgramsWindowData數據，但也許您必須使用ValueConverter才能使綁定起作用。

因此請注意，當您的Viewmodels數據與Views數據不兼容時，盡管綁定路徑設置正確，但是綁定將不起作用。

希望這可以幫助 ：）